Power driven typewriter

ABSTRACT

This invention relates to a power driven typewriter characterized in that too long of depression of the key lever will not cause &#39;&#39;&#39;&#39;repeat&#39;&#39;&#39;&#39; typing, the typing pressure exerted by the type bar on the platen can be adjusted easily and repeat typing may be effected by any key lever by simple means. Further, as compared with ordinary power driven type-writers, the construction is much simpler and less costly.

United States Patent [191 [111 3,923,136 Nakajima Dec. 2, 1975 [54] POWER DRIVEN TYPEWRITER 3,706,366 12/1972 Hishida ct a1 197/17 [76] Inventor: Nobuyoshi Nakajima, 5, 3.738.470 6/1973 Osaka 197/17 Hakozakicho 4'chome Nihonba Primarv ExaminerEdgar S Burr Chyuoku Tokyo Japan Assistant Examiner R. T. Rader [22] Filed: Sept. 14, 1973 211 Appl. No.: 397,251 1571 ABSTRACT This invention relates to a power driven typewriter 52] U S Cl 197 I17 characterized in that too long of depression of the key I u .0 v u n o l l s I u u I l u u l I I I s u l l I u n u l a I u u u II 51 Int Cl B41J 23/08 p [58] 17 27 16 sure exerted by the type bar on the platen can be adle 0 care l justed easily and repeat typing may be effected by any References Cited key lever by simple means. I v

UNITED STATES PATENTS Further, as compared with ordinary power driven type-writers, the construction 1s much simpler and 3,342,295 9/1967 Hishida 197/17 less costly 3,638,775 2/l972 Hishida et al 197/17 3,642,110 2/1972 Hishida et al 197/17 X 3 Claims, 5 Drawing Figures H r l 6 '77:

u 5 lb la I U.S. Patent Dec. 2, 1975 Sheet10f2 3,923,136

U.S. Patent Dec. 2, 1975 Sheet 2 of2 3,923

FIG. 3

1 POWER DRIVEN TYPEWRITER BACKGROUND OF THE, mvENfrio N This invention relates to a power driven typewriter. Accordingto this invention, involun tary repe at typing owing to too long depression of the key lever by hand may be avoided and the depression of the key lever as well as the typing pressure on the platen may be adjusted simply.

SUMMARY OF THE PRESENT INVENTION This invention comprises a key lever mounted on a horizontal shaft and having a downward bent portion at one end thereof in the form of an inverted L which is provided with a jut at the bottom, an actuating lever mounted on another horizontal shaft and connected to a type bar by means of a link, a lever hanging freely from the actuating lever and having a jut adapted to engage with vanes provided radially around a rotating driving roll and provided with an angle piece pivoted to one side, the angle piece being adapted to engage with the jut provided in the downward bent portion of the key lever, an adjustable stopper for limiting the forward movement of the hanging lever, an adjustable means for limiting the depression of the key lever and a constantly rotating driving roll having a number of radial vanes around the same.

DESCRIPTION OF THE DRAWINGS The invention is illustrated in a preferred embodiment in the accompanying drawing, in which,

FIG.1 shows for simplicity only one key lever and its correlated parts in their initial positions,

FIG.2 shows the same parts as FIG.1 at the moment.

of an early stage of depressing key lever,

FIG.3 shows the same parts as FIG.2 when typing is effected,

FIG.4 shows the hanging lever suspended to move forward through the engagement of the angle piece and jut formed at the base of the inverted L-formed downward bent portion of the key lever, and

FIG. shows a perspective view of angle piece 11 depicted in FIGS. 1-4 for the purpose of clarity.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the embodiment illustrated, key lever 1 passes through slits provided in both sides of horizontal casing 3 and is mounted on horizontal shaft 4 within said casing. One end of said key lever is bent downward in the form of an inverted L and urged by a spring 16 to the rear side of the casing 3. Within said casing, actuating lever 6 is mounted on a horizontal shaft 5. One end of said lever is connected to type bar 8 pivoted at 20 through a link 7. AT the middle of the actuating lever 6, lever 9 is hung freely at 10. Said lever is provided with a jut 9a and on one side of said lever, an angle piece 11 is pivoted at 12 and is urged to frame 14 arranged below lever by a spring 13. 15 is a stopper adjustably attached to the base of frame 14. 18 is a plate which is adjustably attached to the rear side of the casing 3 and is provided with guide slit 17 under which a metal plate 19 is attached to limit the depression of key lever 1. 2 is a constantly rotating driving roll having a number of radial vanes arranged around the same.

The function of the'above mentioned mechanism is as follows: When the key is depressed, key lever 1 rotates clockwise around the shaft 4 and its jut lb which is provided at the lower end of the inverted L-form portion 1a strikes the bent edge 11a 'of angle piece 11 so asto swing the hanging lever 9 forward'until the end 9b of said lever is brought into contact with the stopper 15. At this moment, as the angular jut 9a is moved into the path of the rotating vanes provided around the rotating roll 2, one of said vanes engages with said jut and gives a sudden clockwise jerk to the lever 6 around the shaft 5 whereby type lever 8 suddenly swings counterclockwise around the shaft 20 and strikes forcibly on the platen (refer to H682 and 3) so as to effect printing.

As soon as printing is done, type bar 8 and lever 6 return to the initial positions while key lever l is still depressed. At the same time, while the hanging lever 9 is returning to its initial position by means of spring 13,

20 jut 1b catches the bent edge 11a of angle piece 11 (refer F164) and retains said hanging lever remotely from the stopper 15. Thus, it is obvious from the above that slow touch that is unduly long depression of keywould not permit double printing. As soon as the finger is removed from the key, jut 1b disengages from the angle piece 11 whereby hanging lever 9a may return to the initial position as shown in F161.

As is clear from the above, as the stopper 15 limits the forward movement of the hanging lever 9, striking pressure of type bar on the platen may be easily adjusted by moving the stopper back or forth. Further, repeat printing is possible by lowering the plate 18 so as to increase the depressing length of key lever.

What I claim:

1. A power driven typewriter comprising a frame; a casing; a key lever having a downwardly bent portion at one end thereof in the form of an inverted L, said key lever being pivotally mounted to said frame and being pivotable between an actuating position and an at rest position; an actuating lever pivotally mounted to said frame adjacent said key lever; a type lever pivotally mounted to said frame and being pivotal between an at rest position and a type producing position; linkage means connecting said actuating lever and said type lever to produce pivotal movement of said type lever from said at rest position to said type producing position upon pivotal movement of said actuating lever from an at rest position to an actuating position; a third lever hanging freely from said actuating lever; a drum member mounted to said frame and having vanes carried by said drum to be rotatably movable therewith, said third lever having a jut portion movable into the path of said vanes of said drum member; means biasing said third lever to a position in which said jut member is spaced from said vanes, said third lever having an angle piece pivotally mounted thereteo intermediate said actuating lever and said jut portion in a position to be engaged by said downwardly bent portion of said key lever upon pivotal movement of said key lever from said at rest position to an actuating position, movement of said key lever to said actuating position being operable to move said jut portion of said third lever into engagement with said vanes to thereby pivot said actuating lever from said at rest position to said actuating position, said downwardly bent portion of said key lever having a recessed portion adapted to receive said angle piece after engagement of said jut portion of said third end plate being resilient and engaging said key lever to limit depression thereof.

3. The typwriter as defined in claim 1 and including means carried by said frame and engageable with said third lever to limit movement of said third lever toward said drum, said means being adjustably mounted to said frame. 

1. A power driven typewriter comprising a frame; a casing; a key lever having a downwardly bent portion at one end thereof in the form of an inverted L, said key lever being pivotally mounted to said frame and being pivotable between an actuating position and an at rest position; an actuating lever pivotally mounted to said frame adjacent said key lever; a type lever pivotally mounted to said frame and being pivotal between an at rest position and a type producing position; linkage means connecting said actuating lever and said type lever to produce pivotal movement of said type lever from said at rest position to said type producing position upon pivotal movement of said actuating lever from an at rest position to an actuating position; a third lever hanging freely from said actuating lever; a drum member mounted to said frame and having vanes carried by said drum to be rotatably movable therewith, said third lever having a jut portion movable into the path of said vanes of said drum member; means biasing said third lever to a position in which said jut member is spaced from said vanes, said third lever having an angle piece pivotally mounted thereteo intermediate said actuating lever and said jut portion in a position to be engaged by said downwardly bent portion of said key lever upon pivotal movement of said key lever from said at rest position to an actuating position, movement of said key lever to said actuating position being operable to move said jut portion of said third lever into engagement with said vanes to thereby pivot said actuating lever from said at rest position to said actuating position, said downwardly bent portion of said key lever having a recessed portion adapted to receive said angle piece after engagement of said jut portion of said third lever with the vanes of said drum member to permit said jut member to be spaced from said vanes until said key lever is returned to said at rest position.
 2. The typewriter as defined in claim 1 and including means carried by said casing for limiting the pivotal movement of said key lever, said means comprising a first plate adjustably attached to said casing, said plate being provided with a guide slit, a second plate attached to said first plate under said guide slit, said sEcond plate being resilient and engaging said key lever to limit depression thereof.
 3. The typwriter as defined in claim 1 and including means carried by said frame and engageable with said third lever to limit movement of said third lever toward said drum, said means being adjustably mounted to said frame. 